CN112987232A

CN112987232A - Optical lens and electronic device

Info

Publication number: CN112987232A
Application number: CN201911212113.7A
Authority: CN
Inventors: 王东方; 李季; 姚波
Original assignee: Ningbo Sunny Automotive Optech Co Ltd
Current assignee: Ningbo Sunny Automotive Optech Co Ltd
Priority date: 2019-12-02
Filing date: 2019-12-02
Publication date: 2021-06-18

Abstract

The application discloses an optical lens and an electronic device including the same. The optical lens sequentially comprises from an object side to an image side along an optical axis: a first lens having a negative focal power, wherein the object-side surface is a convex surface and the image-side surface is a concave surface; a second lens having optical power; a third lens with positive focal power, wherein the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a convex surface; the fourth lens has positive focal power, and the image side surface of the fourth lens is a convex surface; and a fifth lens having a negative refractive power, the object side surface of which is concave. The optical lens can realize at least one of the advantages of high resolution, low cost, good temperature adaptability, miniaturization, easy installation and the like.

Description

Optical lens and electronic device

Technical Field

The present disclosure relates to the field of optical elements, and more particularly, to an optical lens and an electronic device.

Background

In recent years, with the rapid development of the automobile industry, the vehicle-mounted lens is widely applied to an auxiliary driving system. Meanwhile, the performance requirements of the market on the vehicle-mounted lens become higher and higher. The vehicle-mounted lens in the technical aspect tends to be high, fine and sharp. On the basis of meeting the imaging quality requirement of the vehicle-mounted lens, the market has smaller and smaller requirement on the whole size of the lens. The optical lens with smaller size is convenient to mount and does not influence the integral interior decoration effect of the automobile. When the vehicle-mounted lens is applied specifically, the temperature of the application environment of the vehicle-mounted lens is changed continuously, for example, the temperature is high in summer and low in winter. This makes the application environment of the onboard lens likely to have a large temperature difference. When the common lens is applied in the environment with large temperature difference, image plane deviation can be generated, so that imaging blur of the lens occurs, and normal use is influenced.

Disclosure of Invention

An aspect of the present application provides an optical lens, in order from an object side to an image side along an optical axis, comprising: the lens comprises a first lens, a second lens, a third lens, a fourth lens and a fifth lens, wherein the first lens has negative focal power, the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a concave surface; the second lens has optical power; the third lens has positive focal power, the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a convex surface; the fourth lens has positive focal power, and the image side surface of the fourth lens is a convex surface; and the fifth lens has negative focal power, and the object side surface of the fifth lens is a concave surface.

In one embodiment, the object-side surface of the second lens element is convex and the image-side surface of the second lens element is concave.

In one embodiment, the object-side surface of the second lens element is concave and the image-side surface of the second lens element is convex.

In one embodiment, the object-side surface of the second lens element is convex, and the image-side surface of the second lens element is convex.

In one embodiment, the object side surface of the fourth lens is convex.

In one embodiment, the object side surface of the fourth lens is concave.

In one embodiment, the image-side surface of the fifth lens element is convex.

In one embodiment, the image side surface of the fifth lens is concave.

In one embodiment, the fourth lens and the fifth lens are cemented to form a cemented lens.

In one embodiment, a distance TTL between an object side surface of the first lens element and an imaging surface of the optical lens on the optical axis, a maximum field angle FOV of the optical lens, and an image height H corresponding to the maximum field angle FOV satisfy: TTL/H/FOV is less than or equal to 0.03.

In one embodiment, the radius of curvature R1 of the object-side surface of the first lens and the radius of curvature R2 of the image-side surface of the first lens satisfy: the ratio of R1 to R2 is less than or equal to 15.

In one embodiment, a maximum field angle FOV of the optical lens, a maximum clear aperture D of an object-side surface of the first lens corresponding to the maximum field angle FOV, and an image height H corresponding to the maximum field angle FOV satisfy: D/H/FOV is less than or equal to 0.025.

In one embodiment, a distance BFL between an image side surface of the fifth lens element and an image plane of the optical lens on the optical axis and a distance TTL between an object side surface of the first lens element and the image plane of the optical lens on the optical axis satisfy: BFL/TTL is more than or equal to 0.1.

In one embodiment, the effective focal length F4 of the fourth lens and the effective focal length F5 of the fifth lens satisfy: the ratio of F4 to F5 is less than or equal to 2.5.

In one embodiment, the maximum field angle FOV of the optical lens, the total effective focal length F of the optical lens, and the image height H corresponding to the maximum field angle FOV satisfy: (FOV F)/H.gtoreq.40.

In one embodiment, a radius of curvature R5 of the object-side surface of the third lens and a radius of curvature R6 of the image-side surface of the third lens satisfy: the ratio of R5 to R6 is less than or equal to 2.

In one embodiment, a radius of curvature R8 of an object-side surface of the fourth lens and a radius of curvature R9 of an image-side surface of the fourth lens satisfy: R8/R9 is less than or equal to 2.

In one embodiment, a distance d5 between the image-side surface of the third lens element and the object-side surface of the fourth lens element on the optical axis and a distance TTL between the object-side surface of the first lens element and the image plane of the optical lens element on the optical axis satisfy: d5/TTL is less than or equal to 0.1.

In one embodiment, the total effective focal length F of the optical lens and the radius of curvature R1 of the object side surface of the first lens satisfy: and the | F/R1| ≧ 0.075.

Another aspect of the present disclosure provides an optical lens, in order from an object side to an image side along an optical axis, comprising: a first lens, a second lens, a third lens, a fourth lens and a fifth lens, the first lens having a negative focal power; the second lens has optical power; the third lens has positive optical power; the fourth lens has positive optical power; and the fifth lens has a negative optical power; wherein a radius of curvature R8 of an object-side surface of the fourth lens and a radius of curvature R9 of an image-side surface of the fourth lens satisfy: R8/R9 is more than or equal to 2.7.

In one embodiment, the object-side surface of the first lens element is convex and the image-side surface of the first lens element is concave.

In one embodiment, the object-side surface of the third lens element is convex, and the image-side surface of the third lens element is convex.

In one embodiment, the object-side surface of the fourth lens element is convex, and the image-side surface of the fourth lens element is convex.

In one embodiment, the object-side surface of the fourth lens element is concave, and the image-side surface of the fourth lens element is convex.

In one embodiment, the fifth lens element has a concave object-side surface and a convex image-side surface.

In one embodiment, the object side surface of the fifth lens is concave, and the image side surface of the fifth lens is concave.

Still another aspect of the present application provides an electronic device that may include the optical lens according to the above-described embodiment and an imaging element for converting an optical image formed by the optical lens into an electrical signal.

The optical lens has the advantages that the five lenses are adopted, the shape, the focal power and the like of each lens are optimally set, and the optical lens has at least one beneficial effect of high resolution, low cost, good temperature adaptability, miniaturization, easiness in installation and the like.

Drawings

Other features, objects, and advantages of the present application will become more apparent from the following detailed description of non-limiting embodiments when taken in conjunction with the accompanying drawings. In the drawings:

fig. 1 is a schematic view showing a structure of an optical lens according to embodiment 1 of the present application;

fig. 2 is a schematic structural view showing an optical lens according to embodiment 2 of the present application;

fig. 3 is a schematic structural view showing an optical lens according to embodiment 3 of the present application;

fig. 4 is a schematic structural view showing an optical lens according to embodiment 4 of the present application;

fig. 5 is a schematic structural view showing an optical lens according to embodiment 5 of the present application;

fig. 6 is a schematic structural view showing an optical lens according to embodiment 6 of the present application;

fig. 7 is a schematic structural view showing an optical lens according to embodiment 7 of the present application;

fig. 8 is a schematic structural view showing an optical lens according to embodiment 8 of the present application; and

fig. 9 is a diagram illustrating a half aperture d of a maximum clear aperture corresponding to a maximum field angle of an optical lens according to an embodiment of the present application and an Sg value SAG (rise) corresponding thereto.

Detailed Description

For a better understanding of the present application, various aspects of the present application will be described in more detail with reference to the accompanying drawings. It should be understood that the detailed description is merely illustrative of exemplary embodiments of the present application and does not limit the scope of the present application in any way. Like reference numerals refer to like elements throughout the specification. The expression "and/or" includes any and all combinations of one or more of the associated listed items.

It should be noted that in this specification, the expressions first, second, third, etc. are used only to distinguish one feature from another, and do not represent any limitation on the features. Thus, the first lens discussed below may also be referred to as the second lens or the third lens without departing from the teachings of the present application.

In the drawings, the thickness, size, and shape of the lens have been slightly exaggerated for convenience of explanation. In particular, the shapes of the spherical or aspherical surfaces shown in the drawings are shown by way of example. That is, the shape of the spherical surface or the aspherical surface is not limited to the shape of the spherical surface or the aspherical surface shown in the drawings. The figures are purely diagrammatic and not drawn to scale.

Herein, the paraxial region refers to a region near the optical axis. If the lens surface is convex and the convex position is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the concave position is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the object is called the object side surface of the lens, and the surface of each lens closest to the image side is called the image side surface of the lens.

It will be further understood that the terms "comprises," "comprising," "has," "having," "includes" and/or "including," when used in this specification, specify the presence of stated features, elements, and/or components, but do not preclude the presence or addition of one or more other features, elements, components, and/or groups thereof. Moreover, when a statement such as "at least one of" appears after a list of listed features, the entirety of the listed features is modified rather than modifying individual elements in the list. Furthermore, when describing embodiments of the present application, the use of "may" mean "one or more embodiments of the present application. Also, the term "exemplary" is intended to refer to an example or illustration.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present application will be described in detail below with reference to the embodiments with reference to the attached drawings.

The features, principles and other aspects of the present application are described in detail below.

In an exemplary embodiment, the optical lens includes, for example, five lenses having optical powers, i.e., a first lens, a second lens, a third lens, a fourth lens, and a fifth lens. The five lenses are arranged along the optical axis in sequence from the object side to the image side.

In an exemplary embodiment, the optical lens may further include a photosensitive element disposed on the image plane. Alternatively, the photosensitive element provided to the imaging surface may be a photosensitive coupling element (CCD) or a complementary metal oxide semiconductor element (CMOS).

The first lens may have a negative power and have a meniscus shape, its object side may be convex, and its image side may be concave. The arrangement of the cooperation of the focal power and the surface type of the first lens is favorable for reducing the incident angle of incident light on the attack surface of the optical system, and collects more light rays with large viewing angle to enter the rear optical system, thereby increasing the luminous flux and improving the imaging quality of the optical system. In practical application, the vehicle-mounted lens is generally exposed in an external environment, and the meniscus lens protruding towards the object side is beneficial to rain and snow to slide along the lens, so that the service life of the lens is prolonged, and the influence of rain and snow on lens imaging is reduced.

The second lens element can have positive or negative power, and can have a concave object-side surface and a convex image-side surface, or both the object-side surface and the image-side surface can be convex, or the object-side surface can be convex and the image-side surface can be concave. The focal power and the surface shape of the second lens are matched, so that the light rays are favorably dispersed and stably transited, the large-angle light rays are favorably enabled to enter a rear optical system as far as possible, and the illumination of the optical system is improved.

The third lens element can have a positive optical power, and the object-side surface and the image-side surface of the third lens element can be convex at the same time. The third lens is a convergent lens, and the focal power and the surface shape of the convergent lens are matched, so that the convergent lens is beneficial to compressing the angle of incident light to realize light smooth transition and reducing the caliber of the rear-end lens.

The fourth lens element can have a positive power, and can have a convex object-side surface and a convex image-side surface, or can have a concave object-side surface and a convex image-side surface. The arrangement of the focal power and the surface type of the fourth lens is beneficial to converging light rays and adjusting the light ray trend, so that the light ray trend is stable and transits to a rear optical system.

The fifth lens element can have a negative power, can have a concave object-side surface and a convex image-side surface, or can have both a concave object-side surface and a concave image-side surface.

In an exemplary embodiment, a stop for limiting the light beam may be disposed between the third lens and the fourth lens to further improve the imaging quality of the optical lens. The diaphragm is beneficial to effectively collecting light rays entering the optical system and reducing the caliber of a lens at the rear end of the optical system. In the embodiment of the present application, the stop may be disposed in the vicinity of the image side surface of the third lens. It should be noted, however, that the positions of the diaphragms disclosed herein are merely examples and not limitations; in alternative embodiments, the diaphragm may be disposed at other positions according to actual needs.

In an exemplary embodiment, the optical lens according to the present application may further include a filter disposed between the fifth lens and the image plane to filter light rays having different wavelengths, as needed. The optical lens according to the present application may further include a protective glass disposed between the fifth lens and the imaging surface to prevent an element image side (e.g., a chip) of the optical lens from being damaged.

In an exemplary embodiment, the fourth lens and the fifth lens are cemented to form a cemented lens. In this embodiment, the fourth lens with positive focal power is in front, the fifth lens with negative focal power is in back, and the two lenses are matched with each other, which is beneficial to smoothly transition the light transmitted by the third lens to the fifth lens and reduce the total optical length of the system. The gluing mode adopted between the lenses has at least one of the following advantages: self color difference is reduced, and tolerance sensitivity is reduced; the air space between the two lenses is omitted, thereby reducing the total length of the system; the assembling parts between the lenses are reduced, so that the working procedures are reduced, and the cost is reduced; the tolerance sensitivity problems of inclination/core deviation and the like generated in the assembling process of the lens unit are reduced, and the production yield is improved; the light quantity loss caused by reflection among the lenses is reduced, and the illumination is improved; further reducing the curvature of field and effectively correcting the off-axis point aberration of the optical lens. The gluing design shares the whole chromatic aberration correction of the system, effectively corrects the aberration so as to improve the resolving power, and enables the optical system to be compact as a whole and meet the miniaturization requirement.

In an exemplary embodiment, the distance TTL from the object side surface of the first lens to the imaging surface of the optical lens on the optical axis, the maximum field angle FOV of the optical lens, and the image height H corresponding to the maximum field angle FOV satisfy: TTL/H/FOV ≦ 0.03, e.g., TTL/H/FOV ≦ 0.025. The mutual relation among the three is reasonably set, which is beneficial to realizing the miniaturization of the lens, so that the optical system has smaller lens size under the condition of the same imaging surface and the same image height.

In an exemplary embodiment, the radius of curvature R1 of the object-side surface of the first lens and the radius of curvature R2 of the image-side surface of the first lens satisfy: R1/R2| ≦ 15, for example R1/R2| ≦ 12. The proportional relation of the curvature radius of the object side surface of the first lens and the curvature radius of the image side surface of the first lens is reasonably set, the shape of the lens of the first lens is effectively controlled, the first lens is favorable for collecting light rays with larger angles to enter a rear optical system, the front port diameter and the lens volume of the lens are reduced, and the miniaturization of the lens is realized while the resolution of the lens is improved.

In an exemplary embodiment, the maximum field angle FOV of the optical lens, the maximum clear aperture D of the object-side surface of the first lens corresponding to the maximum field angle FOV, and the image height H corresponding to the maximum field angle FOV satisfy: D/H/FOV ≦ 0.025, e.g., D/H/FOV ≦ 0.02. The mutual relation among the three is reasonably set, the front end caliber of the optical lens is favorably reduced, and the miniaturization is realized.

In an exemplary embodiment, a distance BFL on the optical axis from the image-side surface of the fifth lens to the imaging surface of the optical lens and a distance TTL on the optical axis from the object-side surface of the first lens to the imaging surface of the optical lens satisfy: BFL/TTL is ≧ 0.1, e.g., BFL/TTL is ≧ 0.15. In the present application, the distance on the optical axis from the image-side surface of the fifth lens to the imaging surface of the optical lens is also referred to as the back focal length of the optical lens. The proportional relation between the back focal length of the optical lens and the distance from the object side surface of the first lens to the imaging surface of the optical lens on the optical axis is reasonably controlled, the back focal length can be realized on the basis of miniaturization of the optical lens, and the assembly of a lens module is facilitated.

In an exemplary embodiment, the effective focal length F4 of the fourth lens and the effective focal length F5 of the fifth lens satisfy: i F4/F5. ltoreq.2.5, for example, | F4/F5. ltoreq.2. The proportional relation of the effective focal length of the fourth lens and the effective focal length of the fifth lens is reasonably set, so that the focal lengths of the two adjacent lenses are approximately equivalent, light rays in the optical system are smoothly transited, the imaging quality of the optical system is improved, and thermal compensation of the optical lens is improved.

In an exemplary embodiment, the maximum field angle FOV of the optical lens, the total effective focal length F of the optical lens, and the image height H corresponding to the maximum field angle FOV satisfy: (FOV F)/H.gtoreq.40, for example, (FOV F)/H.gtoreq.42. The mutual relation of the three is reasonably set, which is beneficial to the optical lens to have the characteristic of small distortion and has the characteristics of large field angle and long focus.

In an exemplary embodiment, the radius of curvature R5 of the object-side surface of the third lens and the radius of curvature R6 of the image-side surface of the third lens satisfy: R5/R6 ≦ 2, for example R5/R6 ≦ 1.9. The proportional relation between the curvature radius of the object side surface of the third lens and the curvature radius of the image side surface of the third lens is reasonably set, so that the lenses can collect more light rays, and the light flux of the optical system is increased.

In an exemplary embodiment, a radius of curvature R8 of the object-side surface of the fourth lens and a radius of curvature R9 of the image-side surface of the fourth lens satisfy: 2.7 ≦ R8/R9|, e.g., | R8/R9| ≧ 2.9. The curvature radius of the object side surface of the fourth lens and the curvature radius of the image side surface of the fourth lens are reasonably arranged, so that light collected by the third lens is compressed, the light trend is relatively gentle, light is enabled to be smoothly transited to a rear optical system, the aberration of the optical system is effectively reduced, and the imaging quality of the optical system is improved. In this embodiment, if the value of the conditional expression is lower than the lower limit, the incident angle of the light incident on the object-side surface of the fourth lens is increased, and the relative illuminance of the optical system is reduced. Therefore, the proportional relationship between the curvature radius of the object-side surface of the fourth lens element and the curvature radius of the image-side surface of the fourth lens element is set appropriately so as to satisfy the above conditions, which is advantageous for obtaining a bright image with high image quality in the optical system.

In an exemplary embodiment, a distance d5 between the image-side surface of the third lens and the object-side surface of the fourth lens on the optical axis and a distance TTL between the object-side surface of the first lens and the imaging surface of the optical lens on the optical axis satisfy: d5/TTL ≦ 0.1, e.g., d5/TTL ≦ 0.08. The distance between the image side surface of the third lens and the object side surface of the fourth lens on the optical axis is reasonably set to be proportional to the distance between the object side surface of the first lens and the imaging surface of the optical lens on the optical axis, the distance between the third lens and the fourth lens is controlled within a small range, light rays near the diaphragm can be smoothly transited, and the imaging quality of the optical system is improved.

In an exemplary embodiment, the total effective focal length F of the optical lens and the radius of curvature R1 of the object side surface of the first lens satisfy: i F/R1| ≧ 0.075, e.g., | F/R1| ≧ 0.08. The proportional relation between the total effective focal length of the optical lens and the curvature radius of the object side surface of the first lens is reasonably set, so that the change of the refraction angle of incident light in an optical system is facilitated to be relatively mild, the phenomenon that excessive aberration is generated due to too strong light refraction change is avoided, the first lens is facilitated to be manufactured, and the tolerance sensitivity is reduced.

In an exemplary embodiment, a distance TTL on an optical axis from an object side surface of the first lens to an imaging surface of the optical lens and a total effective focal length F of the optical lens satisfy: TTL/F ≦ 7.5, e.g., TTL/F ≦ 7. The proportional relation between the distance from the object side surface of the first lens to the imaging surface of the optical lens on the optical axis and the total effective focal length of the optical lens is reasonably set, so that the optical lens has better performance, and the miniaturization of the lens is realized.

In an exemplary embodiment, a distance TL on the optical axis from the object-side surface of the first lens to the image plane of the fifth lens and a distance d5 on the optical axis from the image-side surface of the third lens to the object-side surface of the fourth lens satisfy: TL/d5 ≧ 9, for example TL/d5 ≧ 11. The distance between the object side surface of the first lens and the imaging surface of the fifth lens on the optical axis and the proportional relation between the distance between the image side surface of the third lens and the object side surface of the fourth lens on the optical axis are reasonably set, and the assembly yield of the lens is favorably improved.

In an exemplary embodiment, the radius of curvature R3 of the object-side surface of the second lens, the radius of curvature R4 of the image-side surface of the second lens, and the total effective focal length F of the optical lens satisfy: i F/R3| + | F/R4| ≦ 5, e.g., | F/R3| + | F/R4| ≦ 3.5. The mutual relation among the curvature radius of the object side surface of the second lens, the curvature radius of the image side surface of the second lens and the total effective focal length of the optical lens is reasonably set, so that the mutual relation meets the conditions, incident rays can be favorably assisted to enter an optical system, astigmatism can be effectively corrected, and the imaging quality is improved.

In an exemplary embodiment, a separation distance d5 between the image-side surface of the third lens and the object-side surface of the fourth lens on the optical axis and a back focal length BFL of the optical lens satisfy: (d5 xBFL)/(d 5+ BFL). ltoreq.1.5, for example, (d5 xBFL)/(d 5+ BFL). ltoreq.1. The proportional relation between the spacing distance of the image side surface of the third lens and the object side surface of the fourth lens on the optical axis and the back focal length of the optical lens is reasonably set, the proportion between the back focal length and the lens space between the third lens and the fourth lens is balanced, the assembly yield of the lens is favorably improved, and the optical system is favorably provided with enough back focal length to place other optical elements so as to increase the design elasticity of the lens.

In an exemplary embodiment, the maximum clear half aperture d9 of the cemented surfaces of the fourth lens and the fifth lens, of which the SAGs 9 of the cemented surfaces of the fourth lens and the fifth lens correspond to the maximum field angle of the optical lens, satisfies: i arctan (SAG9/d9) | ≦ 65, for example, | arctan (SAG9/d9) | ≦ 60. The field angle of the maximum field angle corresponding to the gluing surfaces of the fourth lens and the fifth lens is reasonably set, so that the illumination of an optical system is favorably improved, the resolution quality of the optical system is favorably improved, and the lens processing and assembling are facilitated. In the present embodiment, the saggital height SAG of the object-side surface (image-side surface) of the lens is an on-axis distance from an intersection of the object-side surface (image-side surface) of the lens and the optical axis to a vertex of an effective radius of the object-side surface (image-side surface) of the lens.

In an exemplary embodiment, the combined focal length F45 of the fourth and fifth lenses and the total effective focal length F of the optical lens satisfy: i F45/F ≦ 70, for example, | F45/F ≦ 65. The proportional relation between the combined focal length of the fourth lens and the fifth lens and the total effective focal length of the optical lens is reasonably set, so that the illumination of an optical system is favorably improved, and the distortion is reduced.

In an exemplary embodiment, the third lens may be made of a high refractive index material. For example, the refractive index Nd3 of the material of the third lens satisfies: nd3 is more than or equal to 1.7. The third lens can be made of a material with high refractive index and low Abbe number so as to compensate the axial aberration of the optical system and improve the imaging quality of the optical system. The material selection of the third lens is beneficial to reducing the aperture of the lens, improving the imaging quality, reducing the tolerance sensitivity of the system, improving the production yield and reducing the production cost.

In an exemplary embodiment, the effective focal length F1 of the first lens and the total effective focal length F of the optical lens satisfy: i F1/F ≦ 7, for example, | F1/F ≦ 5. The proportional relation between the effective focal length of the first lens and the total effective focal length of the optical lens is reasonably set, so that more light rays can smoothly enter the optical system, and the illumination of the optical system is improved.

In an exemplary embodiment, the effective focal length F2 of the second lens and the total effective focal length F of the optical lens satisfy: i F2/F ≦ 35, for example, | F2/F ≦ 30. The proportion relation between the effective focal length of the second lens and the total effective focal length of the optical lens is reasonably set, and thermal compensation of an optical system is favorably realized.

In an exemplary embodiment, the effective focal length F3 of the third lens and the total effective focal length F of the optical lens satisfy: i F3/F ≦ 5, for example, | F3/F ≦ 3.5. The proportional relation between the effective focal length of the third lens and the total effective focal length of the optical lens is reasonably set, and the balance of various aberrations in the optical system is facilitated.

In an exemplary embodiment, the effective focal length F4 of the fourth lens and the total effective focal length F of the optical lens satisfy: i F4/F ≦ 8, for example, | F4/F ≦ 5. The proportional relation between the effective focal length of the fourth lens and the total effective focal length of the optical lens is reasonably set, and the balance of various aberrations in the optical system is facilitated.

In an exemplary embodiment, the effective focal length F5 of the fifth lens and the total effective focal length F of the optical lens satisfy: i F5/F ≦ 3, for example, | F5/F ≦ 2. The proportional relation of the effective focal length of the fifth lens and the total effective focal length of the optical lens is reasonably set, so that the fifth lens has a shorter focal length, light collection is facilitated, and the light flux of an optical system is increased.

In an exemplary embodiment, at least one lens of the first to fifth lenses is an aspherical lens. Preferably, the second lens, the fourth lens and the fifth lens are aspheric lenses, which is beneficial to correcting aberration of the system and improving the image resolution quality of the system. The aspheric lens is characterized in that: the curvature varies continuously from the center to the periphery of the lens. Unlike a spherical lens having a constant curvature from the center to the periphery of the lens, an aspherical lens has better curvature radius characteristics, and has advantages of improving distortion aberration and improving astigmatic aberration. After the aspheric lens is adopted, the aberration generated in imaging can be eliminated as much as possible, so that the imaging quality of the lens is improved. The aspheric lens helps to correct system aberration and improve resolving power. In a specific application, the number of the aspheric lenses in the optical imaging lens can be increased or decreased according to the need of image resolution. If the resolution quality of the lens is focused, all the lenses can adopt aspheric lenses.

According to the optical lens provided by the above embodiment of the present application, through the design of materials, surface shapes, reasonable matching of the focal powers of the lenses, the center thicknesses of the lenses and the on-axis distances among the lenses, the high resolving power of the lens is realized on the premise of only using 5 lenses. Through reasonable material selection and collocation and reasonable arrangement of the focal length of the lens, the back focal offset of the lens at high and low temperatures is well controlled, so that the lens meets more severe use environment. Meanwhile, the optical lens meets the requirement of high resolution, realizes miniaturization, has longer back focal length and is convenient to mount.

When focusing attention on the performance stability of the optical lens, all the lenses of the optical lens according to the embodiment of the application can be made of glass materials, so that the optical lens is suitable for different temperature environments, and the optical performance stability is improved. Meanwhile, the optical lens made of glass can inhibit the deviation of the back focus of the optical lens along with the temperature change so as to improve the stability of the system. Meanwhile, the glass material is adopted, so that the problem that the normal use of the lens is influenced due to the imaging blur of the lens caused by high and low temperature changes in the use environment can be avoided.

However, it will be appreciated by those skilled in the art that the number of lenses constituting the lens barrel may be varied to achieve the various results and advantages described in the present specification without departing from the claimed subject matter. For example, although five lenses are exemplified in the embodiment, the optical lens is not limited to include five lenses. The optical lens may also include other numbers of lenses, if desired.

Specific examples of an optical lens applicable to the above-described embodiments are further described below with reference to the drawings.

Example 1

An optical lens according to embodiment 1 of the present application is described below with reference to fig. 1. Fig. 1 shows a schematic structural diagram of an optical lens according to embodiment 1 of the present application.

As shown in fig. 1, the optical lens includes, in order from an object side to an image side along an optical axis, a first lens element L1, a second lens element L2, a third lens element L3, a fourth lens element L4 and a fifth lens element L5.

The first lens L1 is a meniscus lens with negative power, with the object side S1 being convex and the image side S2 being concave. The second lens L2 is a meniscus lens with negative power, with the object side S3 being concave and the image side S4 being convex. The third lens L3 is a biconvex lens with positive power, and has a convex object-side surface S5 and a convex image-side surface S6. The fourth lens element L4 is a biconvex lens with positive power, and has a convex object-side surface S8 and a convex image-side surface S9. The fifth lens L5 is a meniscus lens with negative power, with the object side S9 being concave and the image side S10 being convex.

The optical lens may further include a stop STO, which may be disposed between the third lens L3 and the fourth lens L4 to improve image quality. For example, the stop STO may be disposed near the image side surface S6 of the third lens L3.

In the present embodiment, the object-side and image-side surfaces of the second lens L2, the fourth lens L4, and the fifth lens L5 may each be aspheric.

Optionally, the optical lens may further include a filter L6 and/or a protective glass L6 'having an object side S11 and an image side S12, the filter L6 may be used to correct color deviation and the protective glass L6' may be used to protect the image sensing chip IMA located at the imaging plane S13. The light from the object sequentially passes through the respective surfaces S1 to S12 and is finally imaged on the imaging surface S13.

Table 1 shows a radius of curvature R, a thickness T (it is understood that the thickness T of the row in which S1 is located is the center thickness of the first lens L1, the thickness T of the row in which S2 is located is the air interval d12 between the first lens L1 and the second lens L2, and so on), a refractive index Nd, and an abbe number Vd of each lens of the optical lens of example 1.

TABLE 1

The present embodiment adopts five lenses as an example, and by reasonably distributing the focal power and the surface type of each lens, the center thickness of each lens and the air space between each lens, the lens can have at least one of the advantages of high resolution, miniaturization, small front-end aperture, good temperature performance and the like. Each aspherical surface type Z is defined by the following formula:

wherein Z is the distance rise from the vertex of the aspheric surface when the aspheric surface is at the position with the height of h along the optical axis direction; c is the paraxial curvature of the aspheric surface, c being 1/R (i.e., paraxial curvature c is the inverse of radius of curvature R in table 1 above); k is the conic coefficient conc; A. b, C, D, E, F are all high order term coefficients. Table 2 below shows conic coefficients K and high-order term coefficients A, B, C, D and E of the aspherical lens surfaces S3, S4, S8, S9, and S10 usable in example 1.

TABLE 2

Example 2

An optical lens according to embodiment 2 of the present application is described below with reference to fig. 2. In this embodiment and the following embodiments, descriptions of parts similar to those of embodiment 1 will be omitted for the sake of brevity. Fig. 2 shows a schematic structural diagram of an optical lens according to embodiment 2 of the present application.

As shown in fig. 2, the optical lens includes, in order from an object side to an image side along an optical axis, a first lens element L1, a second lens element L2, a third lens element L3, a fourth lens element L4 and a fifth lens element L5.

The first lens L1 is a meniscus lens with negative power, with the object side S1 being convex and the image side S2 being concave. The second lens L2 is a meniscus lens with positive power, with the object side S3 being concave and the image side S4 being convex. The third lens L3 is a biconvex lens with positive power, and has a convex object-side surface S5 and a convex image-side surface S6. The fourth lens element L4 is a biconvex lens with positive power, and has a convex object-side surface S8 and a convex image-side surface S9. The fifth lens L5 is a meniscus lens with negative power, with the object side S9 being concave and the image side S10 being convex.

Table 3 shows the radius of curvature R, thickness T, refractive index Nd, and abbe number Vd of each lens of the optical lens of example 2.

TABLE 3

Table 4 below gives the conic coefficients K and the high-order term coefficients A, B, C, D and E that can be used for the aspherical lens surfaces S3, S4, S8, S9, and S10 in example 2.

Flour mark

K

A

B

C

D

E

S3

-1.31E+00

-9.34E-04

1.15E-04

2.60E-05

-9.00E-07

8.25E-09

S4

-1.38E+00

7.61E-04

9.27E-06

4.01E-05

-3.38E-06

2.01E-07

S8

-1.06E+02

2.89E-03

-1.07E-04

2.92E-05

-2.62E-06

5.78E-08

S9

-3.89E-01

1.36E-02

1.36E-04

-1.94E-04

2.30E-05

1.23E-06

S10

2.57E+01

5.72E-03

4.05E-05

-3.09E-05

6.31E-06

-2.91E-07

TABLE 4

Example 3

An optical lens according to embodiment 3 of the present application is described below with reference to fig. 3. Fig. 3 shows a schematic structural diagram of an optical lens according to embodiment 3 of the present application.

As shown in fig. 3, the optical lens includes, in order from an object side to an image side along an optical axis, a first lens element L1, a second lens element L2, a third lens element L3, a fourth lens element L4 and a fifth lens element L5.

The first lens L1 is a meniscus lens with negative power, with the object side S1 being convex and the image side S2 being concave. The second lens L2 is a biconvex lens with positive power, and has a convex object-side surface S3 and a convex image-side surface S4. The third lens L3 is a biconvex lens with positive power, and has a convex object-side surface S5 and a convex image-side surface S6. The fourth lens L4 is a meniscus lens with positive power, with the object side S8 being concave and the image side S9 being convex. The fifth lens L5 is a biconcave lens with negative power, and has a concave object-side surface S9 and a concave image-side surface S10.

Table 5 shows the radius of curvature R, thickness T, refractive index Nd, and abbe number Vd of each lens of the optical lens of example 3.

TABLE 5

Table 6 below gives the conic coefficients K and the high-order term coefficients A, B, C, D and E that can be used for the aspherical lens surfaces S3, S4, S8, S9, and S10 in example 3.

Flour mark

K

A

B

C

D

E

3

-2.28E+00

-2.49E-03

7.87E-05

-1.52E-05

3.55E-06

-1.33E-07

4

-1.38E+00

1.22E-03

-1.69E-04

4.75E-05

-4.71E-06

2.76E-07

8

-1.22E+02

-1.85E-03

1.99E-03

-4.97E-04

7.36E-05

-4.00E-06

9

-3.89E-01

5.76E-02

-1.35E-02

1.67E-03

-1.08E-04

2.80E-07

10

6.24E+00

1.65E-02

-2.22E-03

2.75E-04

-1.37E-05

-4.26E-07

TABLE 6

Example 4

An optical lens according to embodiment 4 of the present application is described below with reference to fig. 4. Fig. 4 shows a schematic structural diagram of an optical lens according to embodiment 4 of the present application.

As shown in fig. 4, the optical lens includes, in order from an object side to an image side along an optical axis, a first lens element L1, a second lens element L2, a third lens element L3, a fourth lens element L4 and a fifth lens element L5.

Table 7 shows the radius of curvature R, thickness T, refractive index Nd, and abbe number Vd of each lens of the optical lens of example 4.

TABLE 7

Table 8 below gives the conic coefficients K and the high-order term coefficients A, B, C, D and E that can be used for the aspherical lens surfaces S3, S4, S8, S9, and S10 in example 4.

Flour mark

K

A

B

C

D

E

S3

-3.35E+01

-2.22E-03

8.51E-05

-6.50E-06

2.67E-06

-1.02E-07

S4

-1.38E+00

7.16E-04

-6.24E-05

3.65E-05

-3.82E-06

2.45E-07

S8

-1.22E+02

-2.56E-03

1.98E-03

-4.55E-04

6.14E-05

-3.14E-06

S9

-3.89E-01

4.48E-02

-8.36E-03

9.45E-04

-4.34E-05

7.85E-07

S10

-2.00E+02

1.34E-02

-1.38E-03

1.75E-04

-7.54E-06

-3.96E-07

TABLE 8

Example 5

An optical lens according to embodiment 5 of the present application is described below with reference to fig. 5. Fig. 5 shows a schematic structural diagram of an optical lens according to embodiment 5 of the present application.

As shown in fig. 5, the optical lens includes, in order from an object side to an image side along an optical axis, a first lens element L1, a second lens element L2, a third lens element L3, a fourth lens element L4 and a fifth lens element L5.

The first lens L1 is a meniscus lens with negative power, with the object side S1 being convex and the image side S2 being concave. The second lens L2 is a biconvex lens with positive power, and has a convex object-side surface S3 and a convex image-side surface S4. The third lens L3 is a biconvex lens with positive power, and has a convex object-side surface S5 and a convex image-side surface S6. The fourth lens element L4 is a biconvex lens with positive power, and has a convex object-side surface S8 and a convex image-side surface S9. The fifth lens L5 is a biconcave lens with negative power, and has a concave object-side surface S9 and a concave image-side surface S10.

Optionally, the optical lens may further include a filter L6 and/or a protective glass L6 'having an object side S11 and an image side S12, the filter L6 may be used to correct color deviation and the protective glass L6' may be used to protect the image sensing chip IMA located at the imaging plane S13. The light from the object sequentially passes through the respective surfaces S1 to S12 and is finally imaged on the imaging surface S13. .

Table 9 shows the radius of curvature R, thickness T, refractive index Nd, and abbe number Vd of each lens of the optical lens of example 5.

TABLE 9

The following table 10 gives the conic coefficients K and the high-order term coefficients A, B, C, D and E that can be used for the aspherical lens surfaces S3, S4, S8, S9, and S10 in example 5.

Watch 10

Example 6

An optical lens according to embodiment 6 of the present application is described below with reference to fig. 6. Fig. 6 shows a schematic structural diagram of an optical lens according to embodiment 6 of the present application.

As shown in fig. 6, the optical lens includes, in order from an object side to an image side along an optical axis, a first lens element L1, a second lens element L2, a third lens element L3, a fourth lens element L4 and a fifth lens element L5.

Table 11 shows the radius of curvature R, thickness T, refractive index Nd, and abbe number Vd of each lens of the optical lens of example 6.

TABLE 11

Table 12 below gives the conic coefficients K and the high-order term coefficients A, B, C, D and E that can be used for the aspherical lens surfaces S3, S4, S8, S9, and S10 in example 6.

Flour mark

K

A

B

C

D

E

S3

-9.11E+00

-6.09E-04

2.11E-04

-2.94E-05

3.76E-06

-1.07E-07

S4

-7.85E-01

4.15E-04

-2.45E-05

3.43E-05

-4.01E-06

2.85E-07

S8

-1.26E+02

1.24E-03

4.36E-04

-3.09E-04

7.36E-05

-5.72E-06

S9

-3.88E-01

6.45E-02

-2.00E-02

3.06E-03

-1.92E-04

-4.21E-06

S10

1.64E+01

1.40E-02

-2.95E-03

4.53E-04

-2.45E-05

-5.58E-07

TABLE 12

Example 7

An optical lens according to embodiment 7 of the present application is described below with reference to fig. 7. Fig. 7 shows a schematic structural diagram of an optical lens according to embodiment 7 of the present application.

As shown in fig. 7, the optical lens includes, in order from an object side to an image side along an optical axis, a first lens element L1, a second lens element L2, a third lens element L3, a fourth lens element L4 and a fifth lens element L5.

The first lens L1 is a meniscus lens with negative power, with the object side S1 being convex and the image side S2 being concave. The second lens L2 is a meniscus lens with negative power, with the object side S3 being convex and the image side S4 being concave. The third lens L3 is a biconvex lens with positive power, and has a convex object-side surface S5 and a convex image-side surface S6. The fourth lens element L4 is a biconvex lens with positive power, and has a convex object-side surface S8 and a convex image-side surface S9. The fifth lens L5 is a meniscus lens with negative power, with the object side S9 being concave and the image side S10 being convex.

Table 13 shows the radius of curvature R, thickness T, refractive index Nd, and abbe number Vd of each lens of the optical lens of example 7.

Watch 13

The following table 14 shows conic coefficients K and high-order term coefficients A, B, C, D and E that can be used for the aspherical lens surfaces S3, S4, S8, S9, and S10 in example 7.

TABLE 14

Example 8

An optical lens according to embodiment 8 of the present application is described below with reference to fig. 8. Fig. 8 shows a schematic structural diagram of an optical lens according to embodiment 8 of the present application.

As shown in fig. 8, the optical lens includes, in order from an object side to an image side along an optical axis, a first lens element L1, a second lens element L2, a third lens element L3, a fourth lens element L4 and a fifth lens element L5.

Table 15 shows the radius of curvature R, thickness T, refractive index Nd, and abbe number Vd of each lens of the optical lens of example 8.

Watch 15

The following table 16 gives the conic coefficients K and the high-order term coefficients A, B, C, D and E that can be used for the aspherical lens surfaces S3, S4, S8, S9, and S10 in example 8.

Flour mark

K

A

B

C

D

E

S3

-1.84E+01

2.19E-03

2.15E-04

-4.65E-05

3.71E-06

-1.02E-07

S4

-1.36E+00

8.88E-03

1.95E-04

5.86E-05

-6.40E-06

4.09E-07

S8

-1.29E+02

6.97E-03

-1.28E-03

3.49E-06

3.57E-05

-5.59E-06

S9

-4.10E-01

-5.90E-02

1.66E-02

-2.57E-03

2.03E-04

9.44E-07

S10

1.59E+01

-2.40E-03

2.61E-03

-3.52E-04

2.78E-05

-3.15E-07

TABLE 16

In summary, examples 1 to 8 each satisfy the relationship shown in table 17 below. In table 17, units of D, H, F, BFL, TTL, TL, D5, D34, F1, F2, F3, F4, F5, F45, R1, R2, R3, R4, R5, R6, R7, R8, and R9 are millimeters (mm), and units of FOV and arctan (SAG9/D9) are degrees (°).

TABLE 17

The present application also provides an electronic device that may include the optical lens according to the above-described embodiments of the present application and an imaging element for converting an optical image formed by the optical lens into an electrical signal. The electronic device may be a stand-alone electronic device such as a range finding camera or may be an imaging module integrated on a device such as a range finding device. Furthermore, the electronic device may also be a stand-alone imaging device such as a vehicle-mounted camera, or may be an imaging module integrated on a driving assistance system such as a car.

The above description is only a preferred embodiment of the application and is illustrative of the principles of the technology employed. It will be appreciated by a person skilled in the art that the scope of the invention as referred to in the present application is not limited to the embodiments with a specific combination of the above-mentioned features, but also covers other embodiments with any combination of the above-mentioned features or their equivalents without departing from the inventive concept. For example, the above features may be replaced with (but not limited to) features having similar functions disclosed in the present application.

Claims

1. An optical lens, in order from an object side to an image side along an optical axis, comprising: first lens, second lens, third lens, fourth lens and fifth lens characterized in that:

the first lens has negative focal power, the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a concave surface;

the second lens has optical power;

the third lens has positive focal power, the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a convex surface;

the fourth lens has positive focal power, and the image side surface of the fourth lens is a convex surface; and

the fifth lens has negative focal power, and the object side surface of the fifth lens is a concave surface.

2. An optical lens barrel according to claim 1, wherein the second lens element has a convex object-side surface and a concave image-side surface.

3. An optical lens barrel according to claim 1, wherein the second lens element has a concave object-side surface and a convex image-side surface.

4. An optical lens barrel according to claim 1, wherein the second lens element has a convex object-side surface and a convex image-side surface.

5. An optical lens barrel according to claim 1, wherein the object side surface of the fourth lens is convex.

6. An optical lens barrel according to claim 1, wherein the object side surface of the fourth lens is concave.

7. An optical lens barrel according to claim 1, wherein the image side surface of the fifth lens element is convex.

8. An optical lens barrel according to claim 1, wherein the image side surface of the fifth lens element is concave.

9. An optical lens, in order from an object side to an image side along an optical axis, comprising: first lens, second lens, third lens, fourth lens and fifth lens characterized in that:

the first lens has a negative optical power;

the second lens has optical power;

the third lens has positive optical power;

the fourth lens has positive optical power; and

the fifth lens has a negative optical power; wherein a radius of curvature R8 of an object-side surface of the fourth lens and a radius of curvature R9 of an image-side surface of the fourth lens satisfy:

2.7≤|R8/R9|。

10. an electronic apparatus characterized by comprising the optical lens according to claim 1 or 9 and an imaging element for converting an optical image formed by the optical lens into an electric signal.